PBDB Taxon

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Trinucleida

Trilobita - Trinucleida

Taxonomy

Trinucleina was named by Swinnerton (1915). It is not extant.

It was reranked as the order Trinucleida by Bignon et al. (2020).

It was assigned to Ptychopariida by Harrington and Leanza (1957); and to Libristoma by Bignon et al. (2020).

Subtaxa

Alsataspididae, Dionididae, Raphiophoridae, Trinucleidae

Synonymy list

Year	Name and author
1915	Trinucleina Swinnerton
1957	Trinucleina Harrington and Leanza
2020	Trinucleida Bignon et al. p. 1072

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Rank	Name	Author
kingdom	Animalia	()
—	Bilateria
—	Eubilateria	Ax 1987
—	Protostomia
—	Ecdysozoa	Aguinaldo et al. 1997
—	Panarthropoda

Rank	Name	Author
phylum	Arthropoda	Latreille 1829
subphylum	Artiopoda	(Hou and Bergstrom)
class	Trilobita	Walch 1771
subclass	Libristoma
order	Trinucleida	(Swinnerton 1915)
order	Trinucleida	(Swinnerton 1915)

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Or. †Trinucleida Swinnerton 1915

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Fm. †Alsataspididae Turner 1940

G. †Araiopleura Harrington and Leanza 1957

†Araiopleura reticulata Harrington and Leanza 1957

†Araiopleura stephani Rushton 1982

G. †Clavatellus Poletaeva 1955

G. †Falanaspis Tjernvik 1956

†Falanaspis aliena Tjernvik 1956

†Falanaspis extensa Fortey 1975

G. †Gaoloupingia Yuan and Yin 1998

†Gaoloupingia gaoloupingensis Yuan and Yin 1998

†Gaoloupingia triangularis Yuan and Yin 1998

G. †Jegorovaia Lu 1964

†Jegorovaia convexa Lu and Chien 1974

†Jegorovaia expansa Lu 1964

G. †Joshuaspis Choi et al. 2008

†Joshuaspis parvus Choi et al. 2008

G. †Macharia Choi et al. 2008

†Macharia pengi Choi et al. 2008

G. †Orometopus Broegger 1898

†Orometopus notatifrons Harrington and Leanza 1957

G. †Pagometopus Henningsmoen 1959

G. †Palquiella Suárez-Soruco 1975

G. †Rhadinopleura Harrington and Leanza 1957

†Rhadinopleura eurycephala Harrington and Leanza 1957

G. †Seleneceme Clark 1924

Invalid names: Alsataspis Turner 1940 [synonym]

G. †Skljarella Petrunina 1973

†Skljarella cracens Fortey and Owens 1991

†Skljarella expansa Bao and Jago 2000

†Skljarella hunanensis Peng 1984

†Skljarella sulcifera Peng 1992

G. †Spirantyx Whittard 1961

G. †Torifera Wolfart 1974

†Torifera abrupta Peng et al. 2004

†Torifera jelli Peng et al. 2009

†Torifera paraconvexa Yang 1978

†Torifera taoyuanensis Peng 1987

†Torifera tuma Yang 1977

Invalid names: Xiangia Peng 1987 [synonym]

G. †Yumenaspis Chang 1960

G. †Zacompsus Raymond 1924

†Zacompsus levisensis Rasetti 1944

Invalid names: Hapalopleuridae Harrington and Leanza 1957 [invalid subgroup], Jegorovaiidae [invalid subgroup], Orometopidae Hupe 1955 [invalid subgroup]

Fm. †Dionididae Gürich 1907

G. †Aethedionide Zhou and Ju 1983

G. †Digrypos Kobayashi 1940

G. †Dionide Barrande 1847

†Dionide formosa Barrande 1846

†Dionide formosa anatolica Dean 1967

†Dionide holdeni Raymond 1925

Invalid names: Dionide contrita Raymond 1920 [synonym]

†Dionide jubata Raymond 1925

†Dionide magnifica Owen and Bruton 1980

†Dionide mareki Henry and Romano 1978

†Dionide miaopoensis Lu 1975

†Dionide prima Kloucek 1917

†Dionide semicircula Owen 1981

Invalid names: Dionidepyga Snajdr 1981 [synonym]

G. †Dionidella Prantl and Pribyl 1950

Subg. †Dionidella (Huangnigangia) Han and Ju 1983

†Dionidella incisa Prantl and Přibyl 1949

Invalid names: Dionidella (Huangnigangia) subquadrata Han and Ju 1983 [synonym]

†Dionidella venusta Zhou et al. 2014

G. †Tongxinaspis Zhou 1981

G. †Trinucleoides Raymond 1917

Fm. †Raphiophoridae Angelin 1854

G. †Ampyxina Ullrich 1922

†Ampyxina bellatula Savage 1917

†Ampyxina lanceola Whittington 1959

†Ampyxina powelli Raymond 1920

Invalid names: Ampyxina scarabeus Butts 1941 [synonym]

G. †Ellsaspis Rasetti 1945

Subfm. †Endymioniinae Raymond 1920

G. †Anisonotella Whittington 1965

†Anisonotella glacialis Billings 1865

Invalid names: Anisonotus Raymond 1920 [replaced]

G. †Carinocranium Dean 1989

†Carinocranium cariniferum Dean 1989

G. †Endymionia Billings 1865

†Endymionia canningi Legg 1976

†Endymionia clavaria Fortey 1975

†Endymionia meeki Billings 1862

†Endymionia raymondi Whittington 1965

†Endymionia schucherti Raymond 1920

†Endymionia semielliptica Chang and Fan 1960

Invalid names: Endymionia circularis Zhang 1981 [synonym], Endymionia nodosa Zhang 1981 [synonym], Endymionia ordosensis Lu in Lu et al 1976 [synonym]

Invalid names: Endymion Billings 1862 [replaced]

G. †Lehnertia Vaccari et al. 2006

†Lehnertia nawisapa Vaccari et al. 2006

G. †Pytine Fortey 1975

†Pytine brevicauda Wiman 1905

†Pytine graia Fortey 1975

G. †Salteria Thomson 1864

†Salteria primaeva Wyville Thomson 1864

Invalid names: Salteria americana Cooper 1953 [synonym]

Invalid names: Erinnys Salter 1865 [replaced]

G. †Kanlingia Zhang 1981

†Kanlingia kalpinensis Zhang 1981

G. †Lonchodomas Angelin 1854

Subg. †Lonchodomas (Foliopyge) Perfiliev and Levitsky 1963

†Lonchodomas blackstonensis Legg 1976

†Lonchodomas carinatus Cooper 1953

†Lonchodomas chaziensis Shaw 1968

†Lonchodomas clavulus Whittington 1965

†Lonchodomas coagmentatum Tripp 1980

†Lonchodomas depressus Brogger 1887

†Lonchodomas halli Billings 1861

†Lonchodomas normalis Billings 1865

†Lonchodomas paenepennatus Ross 1970

†Lonchodomas pennatus Latouche 1884

†Lonchodomas politus Raymond 1925

†Lonchodomas portlocki Barrande 1846

†Lonchodomas punctatus Cooper 1953

†Lonchodomas retrolatus Ross and Barnes 1967

†Lonchodomas rostratus Sars 1835

†Lonchodomas sublaevis Raymond 1925

†Lonchodomas suriensis Harrington and Leanza 1957

†Lonchodomas tenuis Nielsen 1995

†Lonchodomas tumidus Forbes 1849

†Lonchodomas volborthi Schmidt 1894

†Lonchodomas yohi Sun 1931

G. †Malinaspis Andreeva 1985

G. †Malongullia Webby and Moors 1970

†Malongullia oepiki Webby et al. 1970

†Malongullia sinensis Wei et al. 2023

†Malongullia zhenxiongensis Wei et al. 2023

Invalid names: Ampyxinops Zhang 1979 [synonym]

G. †Nambeetella Legg 1976

†Nambeetella embolion Fortey and Shergold 1984

†Nambeetella fitzroyensis Legg 1976

G. †Nanshanaspis Zhang and Fan 1960

†Nanshanaspis levis Chang and Fan 1960

†Nanshanaspis rotundata Zhang 1988

†Nanshanaspis tarimuensis Zhang 1981

Invalid names: Caganaspis Kolobova 1968 [synonym], Kongqiaoheia Zhang 1988 [synonym]

G. †Pseudampyxina Ju 1983

G. †Raphioampyx Baldis and Baldis 1995

Subfm. †Raphiophorinae Angelin 1854

G. †Ampyx Dalman 1827

Subg. †Ampyx (Parampyx) Zhang 1981

†Ampyx abnormalis Yi 1957

†Ampyx americanus Safford and Vogdes 1889

†Ampyx binodulosus Reed 1896

†Ampyx camurus Raymond 1925

†Ampyx cetsarum Fortey and Owens 1978

†Ampyx compactus Ross and Barnes 1967

†Ampyx delicatulus Fortey 1975

†Ampyx foveolatus Angelin 1854

†Ampyx laeviusculus Billings 1865

†Ampyx lobatus Cooper 1953

†Ampyx nasutus Dalman 1827

†Ampyx porcus Fortey 1975

†Ampyx priscus Thoral 1935

†Ampyx punctolineatus Zhou and Fortey 1986

†Ampyx spongiosus Fortey 1975

†Ampyx toxotis Fortey 1975

†Ampyx virginiensis Cooper 1953

†Ampyx walcotti Kobayashi 1955

Invalid names: Brachyampyx Forbes 1849 [objective synonym]

G. †Ampyxella Dean 1960

†Ampyxella aculeata Angelin 1854

G. †Ampyxinella Korleva 1959

†Ampyxinella costata Lu 1975

†Ampyxinella rotundata Zhang 1979

Invalid names: Ampyxinella circulare Zhang 1981 [synonym], Ampyxinella ovata Zhang 1979 [synonym]

G. †Ampyxoides Whittington 1965

†Ampyxoides inermis Fortey 1975

†Ampyxoides occipitalis Dean 1973

†Ampyxoides semicostatus Billings 1865

G. †Bulbaspis Chugaeva 1956

G. †Cnemidopyge Whittard 1955

†Cnemidopyge bisecta Elles 1940

†Cnemidopyge costata Boeck 1838

†Cnemidopyge nuda Murchison 1839

†Cnemidopyge nuda granulata Whittard 1955

Invalid names: Ampyx latus M'Coy 1851 [synonym]

†Cnemidopyge parva Hughes 1969

†Cnemidopyge tenuis Kennedy 1988

G. †Damghanampyx Ghobadi Pour et al. 2007

†Damghanampyx ginteri Ghobadi Pour et al. 2007

G. †Edmundsonia Cooper 1953

†Edmundsonia typa Cooper 1953

G. †Globampyx Fortey 1975

†Globampyx popovkiensis Balashova 1966

†Globampyx sexsegmentatus Fortey et al. 2024

†Globampyx sinalae Norford and Ross 1978

†Globampyx trinucleoides Fortey 1975

G. †Mendolaspis Rusconi 1951

†Mendolaspis doidyx Fortey 1975

†Mendolaspis paradoidyx Zhang 1981

†Mendolaspis salagastensis Rusconi 1951

G. †Miaopopsis Lu 1965

G. †Raphiophorus Angelin 1854

†Raphiophorus lamasi Harrington and Leanza 1957

†Raphiophorus quadricostatus Emmons 1855

G. †Rhombampyx Fortey 1975

†Rhombampyx chinensis Weller 1913

†Rhombampyx glaber Poulsen 1965

†Rhombampyx rhombos Fortey 1975

†Rhombampyx tragula Fortey 1975

†Rhombampyx yii Lu 1965

G. †Raymondella Reed 1935

†Raymondella elegans Cooper 1953

†Raymondella macconochiei Nicholson and Etheridge 1879

†Raymondella nevadensis Ross and Shaw 1972

Invalid names: Reedaspis Prantl and Pribyl 1949 [objective synonym]

G. †Sinampyxina Sheng 1974

G. †Taklamakania Zhang 1980

†Taklamakania granulosus Zhang 1981

†Taklamakania paucisegmentatus Wei et al. 2023

†Taklamakania tarimensis Zhang 1979

Invalid names: Ampyx (Parampyx) nanjiangensis Zhang 1981 [synonym]

†Taklamakania xinjiangensis Zhang 1981

Invalid names: Xinjiangia Zhang 1981 [synonym]

Fm. †Trinucleidae Hawle and Corda 1847

G. †Anebolithus Huges and Wright 1970

G. †Auritolithus Holloway et al. 2022

G. †Bergamia Whittard 1955

Invalid names: Bohemaspis Horbringer 1986 [synonym], Brandysops Horbringer 1986 [synonym], Cochliorrhoe Whittard 1966 [synonym]

G. †Bettonolithus Morris 1988

Invalid names: Bettonia Whittard 1956 [replaced]

G. †Botrioides Stetson 1927

G. †Costonia Whittard 1956

Subfm. †Cryptolithinae Angelin 1854

G. †Broeggerolithus Lamont 1935

†Broeggerolithus broeggeri Bancroft 1929

†Broeggerolithus broeggeri ulrichi Bancroft 1949

†Broeggerolithus discors Angelin 1854

†Broeggerolithus nicholsoni Reed 1910

Invalid names: Ulricholithus Bancroft 1949 [synonym]

G. †Cryptolithoides Whittington 1941

†Cryptolithoides reticulatus Ross and Shaw 1972

†Cryptolithoides ulrichi Whittington 1941

G. †Cryptolithus Green 1832

†Cryptolithus recurvus Ulrich 1919

†Cryptolithus tessellatus Green 1832

Invalid names: Cryptolithus lorettensis Foerste 1924 [synonym], Trinucleus bellulus Ulrich 1879 [synonym]

G. †Deanaspis Hughes et al. 1975

†Deanaspis bedinanensis Dean 1967

†Deanaspis goldfussii Barrande 1846

†Deanaspis goldfussii senftenbergii Hawle and Corda 1847

†Deanaspis seftenbergii Hawle and Corda 1847

G. †Decordinaspis Harper and Romano 1967

G. †Eirelithus Lamont 1941

G. †Famatinolithus Harrington and Leanza 1957

†Famatinolithus noticus Harrington and Leanza 1957

G. †Furcalithus Fortey and Owens 1987

G. †Guandacolithus Harrington and Leanza 1957

†Guandacolithus furquei Harrington and Leanza 1957

G. †Gymnostomix Fortey and Owens 1987

G. †Hanchungolithus Lu 1956

†Hanchungolithus richthofeni Kayser 1883

Invalid names: Ichangolithus Lu 1963 [synonym]

G. †Incaia Whittard 1955

G. †Jianxilithus Zhang and Zhou 1876

G. †Lloydolithus Bancroft 1933

G. †Lordshillia Whittard 1966

G. †Marekolithus Shaw 1995

†Marekolithus kosoviensis Marek 1952

G. †Marrolithoides Williams 1948

G. †Marrolithus Bancroft 1929

†Marrolithus orthogonius Dean 1967

G. †Myinda Stubblefield and Bulman 1927

G. †Myindella Hutchison and Ingham 1962

G. †Myttonia Whittard 1955

G. †Nankinolithus Lu 1957

†Nankinolithus granulatus Wahlenberg 1818

G. †Ningkianolithus Lu 1954

Invalid names: Ceratolithus Lu 1959 [synonym]

G. †Novaspis Whittington 1941

G. †Onnia Bancroft 1933

†Onnia goldfussi Barrande 1846

G. †Paratretaspis Dean 1973

G. †Paratrinucleus Whittington 1941

G. †Parkesolithus Campbell and Durham 1970

G. †Protolloydolithus Williams 1948

†Protolloydolithus reticulatus Elles 1940

G. †Reedolithus Bancroft 1929

G. †Reuscholithus Bancroft 1929

G. †Salterolithus Bancroft 1929

Invalid names: Smeathenia Dean 1960 [synonym]

G. †Stapeleyella Whittard 1955

†Stapeleyella inconstans Whittard 1955

G. †Telaeomarrolithus Williams 1948

Invalid names: Fimbriomarrolithus Williams 1948 [objective synonym]

Subfm. †Trinucleinae Hawle and Corda 1847

G. †Iputaspis McCobb and Popov 2017

†Iputaspis stepnyakensis McCobb and Popov 2017

G. †Kimakaspis Ghobadi Pour et al. 2011

†Kimakaspis kovalevskyi Ghobadi Pour et al. 2011

G. †Tretaspis M'Coy 1849

†Tretaspis anderssoni Stormer 1945

†Tretaspis askerensis Owen 1980

†Tretaspis ceriodes Angelin 1854

†Tretaspis ceriodes angelini Stormer 1930

†Tretaspis ceriodes favus Dean 1963

†Tretaspis hadelandica Stormer 1945

†Tretaspis hadelandica hadelandica Stormer 1945

†Tretaspis hadelandica brachystichus Ingham 1970

†Tretaspis hisingeri Owen 1980

†Tretaspis kiaeri Stormer 1930

†Tretaspis latilimba Linnarsson 1869

†Tretaspis latilimbus norvegicus Owen 1980

†Tretaspis moeldenensis Cave 1960

†Tretaspis reticulata Ruedemann 1901

†Tretaspis sagenosus Whittington 1959

†Tretaspis seticornis Hisinger 1840

†Tretaspis seticornis seticornis Hisinger 1840

†Tretaspis seticornis anderssoni Stormer 1945

†Tretaspis sortita Reed 1935

†Tretaspis sortita broeggeri Stormer 1945

G. †Trinucleus Murchison 1839

†Trinucleus acervulosus Raymond 1920

Invalid names: Trinucleus acervulosus Raymond 1925 [synonym]

†Trinucleus conollyi Fortey 2006

†Trinucleus seticornis Hisinger 1840

Invalid names: Edgellia Shaw 1950 [objective synonym]

G. †Whittardolithus Hughes and Addison 1975

G. †Xiushuilithus Zhou 1976

G. †Yinpanolithus Lu and Chang 1974

Invalid names: Hanchungolithinae Lu 1963 [empty], Marrolithinae Hughes 1971 [empty], Microdiscus [nomen vanum], Tretaspidinae Whittington 1941 [empty]

Diagnosis

Reference	Diagnosis
A. Bignon et al. 2020	Usually small ovoid-globular (commutavi) protaspides. Short eyes, when present, con- nected to glabella by eyeridge without palpebral lobe. A long (sag.) glabella compared to its maximal width (tr.). Three or fewer short glabellar furrows. Tubercle on gla- bella or occipital ring. Free cheeks anteriorly fused. Facial sutures are marginal or dorsal. Perforated fringe present in more derived forms. Genal spines long and narrow at base. Distal extremities of thoracic segments pointed. Pygidium triangular or semi-circular, smaller than cephalon, wider (tr.) than long (sag.), with a curved anterior border. Pygidial axis narrow, may extend onto posterior border.